Ice Baths Popular, But Health Claims Not Supported by Evidence
2023-02-14
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1Ice baths are a popular subject on American social media pages.
2Kim Kardashian, Harry Styles, Kristen Bell, Lizzo, and other stars have posted about their cold water experiences.
3Health claims surrounding ice baths include improved mood, increased energy, weight loss and reduced inflammation.
4But the science linked to some of those claims is not very strong.
5Here is what medical evidence, experts and fans say about cold water baths, an activity that dates back hundreds of years.
6Since June 2020, Dan O'Conor has jumped into Lake Michigan almost daily.
7The 55-year-old man lives in the city of Chicago.
8O'Conor used the term endorphins - "feel good" hormones released in reaction to pain, stress, exercise and other activities - to talk about his experience.
9"The endorphin rush ... is an incredible way to wake up and just kind of shock the body and get the engine going," he said on a recent morning when the air temperature was minus-5 Celsius.
10With the lake temperature at 1 degree Celsius, O'Conor did a running jump into the icy gray water.
11His first jump came early in the pandemic.
12O'Conor had too much alcohol and his wife was angry at him.
13She told him to "go jump in the lake."
14The common saying is not usually received as a real command.
15But, O'Conor acted on it.
16He says the water felt good that June day, so he kept jumping in every day following.
17As the water grew colder with seasonal change, the good effect was even greater, he said.
18"My mental health is a lot stronger, a lot brighter. I found some zen down here coming down and jumping into the lake and shocking that body," O'Conor said.
19Dr. Will Cronenwett of Northwestern University's Feinberg medical school tried cold-water immersion once while visiting Scandinavian friends.
20After a sauna, he jumped into the ice-cold water for a few minutes.
21He said it was a powerful experience.
22But Cronenwett says studying cold water immersion with a kind of scientific study known as a randomized controlled trial is difficult.
23This is because it is hard to develop a placebo for cold water baths.
24A placebo is something that has no effect.
25Placebos are important because scientific tests need to compare the possible effect of something with something else that does not have any physical effect.
26There are a few ideas about how cold water immersion affects the mind.
27Cronenwett says it makes the part of the nervous system that controls the resting state more active.
28Such an effect may increase feelings of well-being.
29Cold water immersion also affects the part of the nervous system that controls the fight-or-flight stress reaction.
30Cold water treatment on a usual basis may reduce that reaction.
31So, Cronenwett said, it might help people feel better able to deal with other stresses in their lives, although that is not proven.
32Czech researchers found that cold water immersion can increase blood levels of dopamine - another hormone - by 250 percent.
33High amounts have been linked with paranoia and aggression, noted James Mercer of the Arctic University of Norway.
34Mercer co-wrote a recent scientific paper that examined studies on the treatment.
35Cold water immersion raises blood pressure and increases stress on the heart.
36Studies have shown this is safe for healthy people and the effects are only temporary.
37But sometimes these effects can cause the heart to beat unevenly and can cause death, Cronenwett said.
38People with heart conditions or a family history of early heart disease should talk with a doctor before doing cold water immersion, he said.
39Repeated cold-water immersions during colder seasons have been shown to improve how the body reacts to insulin, a hormone that controls blood sugar levels, Mercer noted.
40This might help reduce the risk of getting diabetes.
41It also might help people with the disease control it.
42More study is required to know for sure.
43Cold water immersion also activates brown fat.
44This tissue helps keep the body warm and helps it control blood sugar and insulin levels.
45It also helps the body burn calories.
46I'm John Russell.
1Ice baths are a popular subject on American social media pages. Kim Kardashian, Harry Styles, Kristen Bell, Lizzo, and other stars have posted about their cold water experiences. 2Health claims surrounding ice baths include improved mood, increased energy, weight loss and reduced inflammation. But the science linked to some of those claims is not very strong. 3Here is what medical evidence, experts and fans say about cold water baths, an activity that dates back hundreds of years. 4The mind 5Since June 2020, Dan O'Conor has jumped into Lake Michigan almost daily. The 55-year-old man lives in the city of Chicago. 6O'Conor used the term endorphins - "feel good" hormones released in reaction to pain, stress, exercise and other activities - to talk about his experience. 7"The endorphin rush ... is an incredible way to wake up and just kind of shock the body and get the engine going," he said on a recent morning when the air temperature was minus-5 Celsius. 8With the lake temperature at 1 degree Celsius, O'Conor did a running jump into the icy gray water. 9His first jump came early in the pandemic. O'Conor had too much alcohol and his wife was angry at him. She told him to "go jump in the lake." The common saying is not usually received as a real command. 10But, O'Conor acted on it. 11He says the water felt good that June day, so he kept jumping in every day following. As the water grew colder with seasonal change, the good effect was even greater, he said. 12"My mental health is a lot stronger, a lot brighter. I found some zen down here coming down and jumping into the lake and shocking that body," O'Conor said. 13Dr. Will Cronenwett of Northwestern University's Feinberg medical school tried cold-water immersion once while visiting Scandinavian friends. After a sauna, he jumped into the ice-cold water for a few minutes. He said it was a powerful experience. 14But Cronenwett says studying cold water immersion with a kind of scientific study known as a randomized controlled trial is difficult. This is because it is hard to develop a placebo for cold water baths. 15A placebo is something that has no effect. Placebos are important because scientific tests need to compare the possible effect of something with something else that does not have any physical effect. 16Possible effects on the mind 17There are a few ideas about how cold water immersion affects the mind. 18Cronenwett says it makes the part of the nervous system that controls the resting state more active. Such an effect may increase feelings of well-being. 19Cold water immersion also affects the part of the nervous system that controls the fight-or-flight stress reaction. Cold water treatment on a usual basis may reduce that reaction. So, Cronenwett said, it might help people feel better able to deal with other stresses in their lives, although that is not proven. 20Czech researchers found that cold water immersion can increase blood levels of dopamine - another hormone - by 250 percent. High amounts have been linked with paranoia and aggression, noted James Mercer of the Arctic University of Norway. Mercer co-wrote a recent scientific paper that examined studies on the treatment. 21The heart 22Cold water immersion raises blood pressure and increases stress on the heart. Studies have shown this is safe for healthy people and the effects are only temporary. 23But sometimes these effects can cause the heart to beat unevenly and can cause death, Cronenwett said. People with heart conditions or a family history of early heart disease should talk with a doctor before doing cold water immersion, he said. 24Metabolism 25Repeated cold-water immersions during colder seasons have been shown to improve how the body reacts to insulin, a hormone that controls blood sugar levels, Mercer noted. 26This might help reduce the risk of getting diabetes. It also might help people with the disease control it. More study is required to know for sure. 27Cold water immersion also activates brown fat. This tissue helps keep the body warm and helps it control blood sugar and insulin levels. It also helps the body burn calories. 28I'm John Russell. 29Lindsey Tanner reported on this story for the Associated Press. John Russell adapted it for VOA Learning English. 30________________________________________________________________________ 31Words in This Story 32hormone - n. a natural substance that is produced in the body and that influences the way the body grows or develops 33zen - n. a state of peace and calm 34immersion - n. the act of putting someone or something completely in a liquid or the state of being completely in a liquid 35sauna - n. a special heated room in which people sit or lie down in order to get hot and sweat 36stress - n. a physical, chemical, or emotional factor that causes bodily or mental tension and may be involved in causing some diseases 37paranoia - n. an unreasonable feeling that people are trying to harm you, do not like you, etc. 38calorie - n. an amount of food having an energy-producing value of one large calorie